Exoplanets Complementary Observations Working Group Chair : M. Deleuil
Goal: organise and coordinate observational efforts for programs using the exoplanet channel. prepare the targets selection + mask allocation prepare the scientific analysis prepare follow-up observations of transit candidates: confirmation & characterization Who is concern? People who intend to use exo-channel data: exoplanet core program + add. programs
Focal plane: N 3.5º Secondary targets mv < 9 2.8º Exoplanet field Main target mv 6 stars with 11 < mv < 16 in principle .. 6000 photometric windows per CCDs : targets should be selected.
A0 F0 G2 K2 M2 Magnitude Spectral type 11 12 13 14 15 characterization of all the stars needed! Targets selection Scientific: - Favourite: late type dwarves Criteria: Environmental: - crowding effects • Instrumental: - the shape of the PSF changes as a function of: • the location of the stars on the CCD • star’s colors • star’s magnitude
Targets selection Scientific: - Favourite: late type dwarves Criteria: Environmental: - crowding effects • Instrumental: - the shape of the PSF changes as a function of: • the location of the stars on the CCD • star’s colors • star’s magnitude stars with 11 < mv < 16 at low galactic latitude : no catalogue provides the spectral classification
Preparatory Observations - Step 1 Exoplanet domain ~20 HD 171834: Potential main target for the astero. program
Preparatory Observations - Step 1 Catalogues: • Used for the spectral classification • will be used for the targets selection for short runs • DENIS/2Mass • USNO-A2 • Hipparcos/Tycho Long runs: (~ 20□) ~ 4 106 stars with mv < 16 UBVRI Photometry - since 2001 - 2.5 INT/La Palma : 24 nights Will be complete at the end 2005 - CFHT/12K a few deep exposures in R filter in order to characterize background stars.
Data gathered in EXODAT Ground-based Observations - Status
The ExoDat Data Base scientific DB for exoplanet channel • Archive the ground-based observations • Cross-correlate these data with existing catalogues • Perform the spectral classification • Validate algorithms: - allocation of the best photometric mask - estimate the contamination for each potential target • Prepare the scientific analysis • Validate the data provided to CoRotSky for the Exoplanet channel
Spectral Classification 1) Dwarf / Giant sorting : Ground – based observations cross-correlated with 2Mass and/or DENIS data
i < 16 AND V-i >1.0 Giants i < 16 AND V-i < 1.0 V-i MS MS i Spectral Classification: exemple HD174866 field Giants V - i Main Seq. i
Spectral Classification 1) Dwarf / Giant sorting : From ground – based observations cross-correlated with 2Mass and/or DENIS data luminosity class – good level of confidence for stars brighter than 15 in R 2) UBVRIJHK data compared with SEDs from a spectral library : Estimate of the spectral type of each star – the 3 “best” solutions are saved. Potential binarity is included.
Typical pre-selected field in the center direction: Typical pre-selected field in the anti-center direction: Additional informations on the target selection process for additional programs.. density of stars with R ≤ 15: ~ 6000 (HD 177552) % overlapping : ~ 30% 4200 potential targets / deg2 i.e. 5880 potential targets per CCD density of stars with R ≤ 15: ~ 3100 (HD 49434) % overlapping : ~ 20% 2480 potential targets / deg2 i.e. 3470 potential targets per CCD
Spectroscopic observations Preparatory Observations - Step 2 Once CCDs position will be fixed .. • GIRAFFE/VLT : observations Dec 2004 & Jan 2005 (Guaranteed time + Open time) A.M. Hubert on monday • VIMOS/VLT V. Repipi on tuesday • Brazilian observational facilities discussion on tuesday Goal : for stars with mv < 15 check & improve the spectral classification identify binaries derive stellar parameters: Teff, logg, vsini .. identify hot Jupiter in COROT fields
Photometric survey: Complementary photometric observations: X-rays observations Preparatory Observations - Step 2 BEST (H. Rauer ) monitoring of the Exo-fields (mv < 14.5) 1 or 2 field per season Interest : binaries identification variable stars identification Geneva system (C. Aerts ) Goal : classification of variable stars BUT FOV 6.5’x6.5’ ! Interest and feasibility to be demonstrated (next CW) (F. Favata ) Interest: stellar activity, identify young stars .. (under study)
ExoDat Data Base Contamination Mask design α,δ + error mag_R … Background mV > 16 Spect. type Logg, vsini, Radius, metal... Spectroscopic obs. α,δ + error mag_U+err mag_B+err mag_V+err mag_R+err mag_I+err mag_J+err mag_H+err mag_K+err Colors Images Spect. type Lum. class Binarity Broad Band Photom. Spect. Classif. Soft. Variability, X-rays.. Ground Surveys + Add Prog. Contamination CoRoTSky catalogues mv < 11
α,δ + error mag_R Background mV > 16 Exo-stars in CoRoTSky Contamination Spect. Type Lum. Class Binarity V_min/V_max α,δ + error mag_B+err mag_V+err mag_R+err mag_I+err + star type catalogues mv < 11 Star type = information from add. programs
Follow-up Observations • Necessary in order to • remove ambiguities, • better characterize the nature of the detected planet • derive accurate spectral parameters of the parent star. Radial velocity measurements
Radial velocity follow-up strategy - 1 • SOPHIE – 1.93m OHP/France Fiber-fed cross-dispersed Echelle spectrograph 1st commissioning by the end of 2005 3 m/s in 1 hour for mv = 12.5 • 2m TLS - TAUTENBOURG Germany • Remove ambiguities • HR Spectrocopy of the parent star • Characterization of all the companions with masses Jupiter • Filter the targets for HARPS and UVES+FLAMES
Radial velocity follow-up strategy - 2 • HARPS – 3.6m La Silla • 3 – 30 M (10 M - 0.1 AU - G0 - mv=14) • 50 nights already allocated in HARPS guaranteed time • Possibility to follow-up immediately a detected transit • Additional nights ESO proposals • UVES+FLAMES – 8.2m Paranal • 0.1 – 1 MJup (0.3 MJup - 0.1 AU - G0 - mv=16) • ESO proposal ~ 12 months of delay…
data analysis - spectral classification observational facilities In conclusion .. We are dealing with a large set of data A lot of work has already been done but help is very welcome